Diversity and pathogenicity of Vibrio spp. populations in freshwater products in Jiangsu Province

In order to investigate the distribution and pathogenicity of Vibrio species in freshwater products in Jiangsu Province,we collected 55 aquatic samples from different sources in parts of Jiangsu Province.After samples processing,we obtained 256 isolates by double TCBS plate separation and purification.Through the identification of biochemical tests and 16S rDNA PCR,several kinds of Vibrio species were isolated including Vibrio parahaemolyticus(74.55%),Vibrio alginolyticus(85.45%),Vibrio harveyi(9.1%),Vibrio aestuarianus(3.6%),Vibrio metschnikovii(5.5%),Vibrio azureus(3.6%),Vibrio natriegens(1.8%),Vibrio diazotrophicus(1.8%) and Vibrio owensii(1.8%),of which no tdh and trh gene was found.Results showed that Jiangsu freshwater products Vibrio species presented diverse distribution,in which,Vibrio parahaemolyticus and Vibrio alginolyticus were the dominate species.The composition and distribution of Vibrio species varied with different regions and different samples.Detection rate of coastal area was obviously higher than that of the inland areas,and the detection rate and populations of Vibrio of fish and shrimps was obviously higher than that of the shell and crabs.The results of Kanagawa test for all strains showed that 35 isolates(15.02%) had significant hemolysis circle.Most KP+ isolates could cause certain level of intestinal fluid accumulation,which suggested these isolates may be pathogenic and could became the potential biological risk factors to human.